Feeding mechanism for rock drills



July 15, v'1941. B.. R. sHEETs FEEDING MECHANISM *FOR IOCK DRILLS Filed sept.` 26, 1940- I N VEN TOR. Blz/107e f2. 67mm l v llll if] IAM) mimi

l ATTORNEY. y

Patented July 15, 1941 UNTED STATES PATENT natie QFFlCE FEEDNG- MECHANISM FOR ROCK DRILLS Barten It. Sheets, Denver, Colo., assignor to Gardner-Denver Company, Quincy, Ill., a corporation of Delaware 14 Claims.

rThis invention reiates to improvements in rook drills and is more particularly directed to means for automatically feeding such drills to and from the work.

The object of the present invention is to provide a novel and efficient means, including the piston hammer of a rock drill, for feeding a unit to and from the Work.

Another object of the invention is to provide means, under control of the operator, including the usual rotation mechanism of a rock drill to move the drill longitudinally of the support, and it further contemplates a structure whereby the rotation of the steel might be rendered effective upon either stroke of the piston hammer, thus establishing feeding of the drill upon the nonrotating strokes of the piston hammer.

Still another object of the invention is to. provide fluid operativev means for moving the rock drill upon its support, `'said means being adapted to move the drill in any longitudinal direction, to lock the drill againstl movement and to free the drill so that it might be moved freely by hand upon the support.

Another object of the invention is to provide automatic feeding means for a drill employing the usual feed screw. The feed screw, however, in this specific embodiment being normally stationary and with which fluid operated means in.- cluding the piston hammer cooperates to move the drill longitudinallyl of the support.

Another object lies in the provision of means whereby the feed screw may be locked against movement or permitted to rotate under any degree of resistance selected by the operator.

Further objects of the invention will hereinafter appear, and toI all of these ends theinvention consists of the features of construction, arrangement of parts and combination of elements, substantially as hereinafter fully described. and claimed in the specification .and shown in the accompanying drawing, in which:

Figure 1 is a longitudinal sectional View disclosing a rock drill mounted upon itssupport, together with means for movingthe drill longitudinally thereof.

Figure 2 is a sectional Viewk on the line 2--2 of Figure 1.

Figure 3 is a. sectional view on the line 3-3 of Figure 1, `and Figure 4 is an end View showing in elevation the rear face of the drill and its support.

Briefly, the* invention hereinabout to be described contemplates the provision of a fluid operated mechanism, including the usual piston hammer of a rock drill, for feeding the drill to and from its Work. It will, of course, be understood that in the operation of a drill .as the steel advances into the work it is the purpose of the feeding device to automatically feed the drill forward maintaining i1; in such relation with the work as to insure the proper striking position of the hammer upon ythe steel at all times.

In the accompanying drawing, the device as shown is a part of the drill, this is merely one adaptation. The structure as disclosed includes means for rotating the piston on eitherof its strokes, thus imparti-ng rotation to the drill steel and having means, effective upon the other strokesl of theY piston, and cooperating with the rotation means for moving the drill longitudinally of the support. It further contemplates selective means whereby the rotation may be made effective upon either the forward or the backward stroke of the piston hammer and movement of the drill on i-tsy support being set in motion upon the other of its strokes. In other words, the invention is directed to a structure whereby the rotation stroke of the piston hammer might be selected and means for moving the drill on the non-rotating strokes of the piston hammer.

In the present embodiment there are provided pavvls by means of which the desired direction of feed might be accomplished and =by reason ofthese pawls being engageable with certain elements of the rotation mechanism, rotation might become effective on either stroke of the piston hammer.'

Referring tothe drawing in detail, the numeral 5 indicates a conventional guide shell having the usual cone 6' by which the shell may be suitably secured to any type of mounting.

As shown in Figure 2, the shell includes upstandi'ng side walls l, the inner faces of which are provided with longitudinally extending grooves 8* constituting guideways in which the rock drill and its feeding device, hereinafter described, are positioned for longitudinal movement.

The shellhas affixed to its rear end, the conventional three bar extension indicated at 9. The guide shell 5. is further provided with a longitudinally positioned threaded shaft or screw I0, the front. end of. which, as shown in Figure 1, is rotatably mounted within a yoke l I, secured to the front end of the guide shell. The rear end of the shaft is receivable within a housing l2 forming a yoke for the rear end of the extension 9 and positioned within this housing is a roller bearing I3 supporting the shaft for free rotation. The

shaft is provided with an extension, the extreme end portion I4 of which is splined as at I5 for the reception of a pair of spaced frictional discs I6 between which is positioned an intermediate disc I'I of the same type, having its outer periphery splined to the housing I2.

Movable within the housing I2 and abutting the rear face of the rear disc I6 is an annular plate i8, the central portion of which is provided with an opening I into which the extended end of the shaft is receivable and around this opening I9 is an annular flange 2@ the interior of which is threaded for the reception of a threaded stub shaft 2|, rotatably supported by a removable end plate of the housing and rotated with respect thereto by a handle 22.

With this structure it will be observed that upon rotation of the handle 22 forward movement of the plate I8 will force the discs I5 and I'I into frictional engagement, thus either locking the shaft against movement or freeing it so that movement might be unrestricted. movement of the shaft may be permitted under any resistance afforded by the frictional engagement between the discs I6 and I'I.

In Figure l the rock drill 23 is of any desired construction being mounted for longitudinal movement within the guide shell 5. In the present embodiment the drill includes the usual iiuid distributing Valve to which fluid iiows from a throttle valve formed in a backhead and a cylinder 24 having the usual outstanding anges 25 slidable within the guideways 8 of the shell 5.

The cylinder 24 has positioned therein the usual reciprocating piston hammer 26 for de- Y liver-ing impact blows to the shank of a drill steel 21, supported and interlocked in any desired manner within a chuck sleeve 28 rotatably mounted in the front housing 2S, suitably secured to the front end of the cylinder '24. Splined to the chuck sleeve 28 is a driven member composed of sleeves 30 and 3|, the latter being interlocked with the shank of the piston hammer 26'. Thus, it is apparent that any rotary movement imparted to the piston hammer 23 will be Ytransmitted to the steel 2l.

As is usual in rock drills of this type, there is provided a rotation mechanism whereby the reciprocating piston might be rotated during any one of its strokes. It is common to provide a rotation mechanism for the piston hammer effective on its rearward stroke. The rearward stroke being generally deemed the non-working stroke of the piston. The present invention, however, contemplates means whereby rotation might be given the piston hammer on either its forward or its rearward stroke depending upon the direction in which automatic movement of the drill is desired. To accomplish this there is provided the usual riiie bar 32 having a head 33 which carries spring pressed pawls 34 engageable with the internal teeth of a ratchet ring 35 rotatable within what will be referred to hereinafter as the feed mechanism housing.

As disclosed in Figure 2 the ratchet ring 35 is provided with external teeth engaged by separate locking means indicated at 35 and 31, the latter being merely a spring pressed pawl tending to prevent movement of the ring 35 in a counterclockwise direction. The locking element 36 is a manually oscillated bar having a portion engageable with the peripherial teeth of the ring 35 and as is apparent the bar 3B when oscillated in one direction will enter between adjacent teeth and If desired,4

denitely lock the ring against movement in either direction.

Secured to the rear end of the cylinder 24 is a housing 38 and a backhead 39, the latter having therein the usual control elements of the drill. The housing 33 receives therein the feed mechanism of the drill including an extension 40 of the rie bar 32, the periphery of which is splined and has interlocked thereto the hub of a gear 4I, shown more clearly in Figure 3.

Referring to Figure 3 it will be observed that this gear 4I is provided with peripherial teeth 42 normally engaged by a spring pressed pawl 43 but which may be moved away from contact with the teeth for a purpose hereinafter set forth. To accomplish this movement of the pawl 43, there is provided a segment 44 having a rack 45 with which a gear segment 45, affixed to the shaft 36, might engage. With this structure it is obvious that upon oscillation of the shaft 36 previously referred to, the segment 44 is moved to either the position disclosed in Figure 3 permitting engagement of the pawl 43 with the gear teeth 42, or to a position where the pawl 43 is free of the teeth 42.

The bar 36 is oscillated within its housing by a handle 55 indicated in Figure 4 of the drawing.

Engaging the teeth 42 of the gear 4I is a smaller pinion 41 transmitting motion from the gear 4I to a larger gear 48 formed integral with the feed nut 49 threadedly engaging the feed shaft I0.

From this structure it is apparent that upon rotation of the riflebar 32 movement is transmitted to the feed nut 49 engageable with the shaft I0, thus causing movement of the rock drill and its feeding mechanism longitudinally of the guide shell. Y

From the foregoing description, let us assume that the operator is desirous of setting the drill in operation so that it will be fed forwardly of the guide shell. T0 accomplish this, the handle 50 of the control bar 36 is moved to such aposition as to permit that portion of the bar shown in Figure 2 to move between the external teeth of the ring 35, locking the ring against movement in either direction and at the same time moving the segment so that it might engage the pawl 43 and move it out of its normal engagement with the peripherial teeth 42 of the gear 4 I With this relation of parts on the forward stroke of the piston hammer 26, the rie bar 32 rotates freely in a counterclockwise direction and by reason of the fact that the gear 4I is splined to the rear end of the rifle bar extension, rotation of this gear will occur, rotating the feed nut 48. Assuming that the shaft I0 is locked against movement, the drill will move forwardly of its support as long as the hammer reciprocates.

On the rearward stroke of the piston hammer, and by reason of the fact that its shank is splined to the steel rotating chuck, rotation will be imparted thereto. 'I'his is accomplished by the usual ratchet pawls engaging the internal teeth of the non-rotating ratchet ring 35 and locking the rifle bar 32 against rotation. Naturally, the hammer follows the fiutes of the bar and rotation of the hammer results.

This condition and relation of parts continues until the drill has reached the limit of its desired movement at which time the lever 50 is then swung to its second position, similar to that indicated in Figure 2, whereupon the effective blow upon the steel and then starts on its backward stroke-thev rifle bar is free to spin in a clockwise direction, moving the feed nut 482- accordingly and effecting rearward movement of tlievdri-ll upon its support.

The foregoing statements ofjoperation are, ofv

course, dependent upon the fact that the feed shaft l is locked against movement, rendering movement of the drill upon i-tssupport at the maximum speed. To control this speed ofv movemyentthe operator Acan by rotating the handle Z2 vary the degree of frictionalengagement between theV discs- IE and Il, thereby permittingv theshaft to rotate either freely or under frictional resistance afforded by the discs. Naturally when the shaft rotates freely there is no movement of the drill upon its support. Then again when resistance is offered to the rotation of the shaft'the degree of its rotation and the Speed at which the drill moves may be determined by the operator.

Movement of the -drill by hand upon its support might be accomplished by either permitting the free rotation of the shaft l) or by throwing the pawl 43 out of engagement with the teeth 42 of the gear 4|.

From the foregoing it is thought that the construction, operation and many advantages of the herein described invention will be apparent to those skilled in the art without further description, and it will be understood that various changes in the size, shape, proportion and minor details of construction may be resorted to without departing from the spirit for sacrificing any of the advantages of the invention.

What I claim is:

1. In a rock drill, the combination of a support having slidable thereon a cylinder and a reciprocating piston hammer within the cylinder for delivering impact blows to the shank of a drill steel, a member supporting the steel in line with the piston and having interlocking relation therewith, selectivemeans for rotating the piston on either of its alternate strokes, and means actuated by the rst said means on the non-rotating strokes of the piston to move the drill longitudinally of the support.

2. In a rock drill, the combination of a support having slidable thereon a cylinder and a reciprocating piston hammer within the cylinder for delivering impact blows to the shank of a drill steel, a member supporting the steel in line with the piston and having interlocking relation therewith, means rotating said piston on alternate strokes, said means being selectively operated to determine the stroke of rotation, and additional means actuated by the first said means on the non-rotating strokes of the piston to move the drill longitudinally of the support.

3. In a rock drill, the combination of a support having slidable thereon a cylinder and a reciprocating piston hammer within the cylinder for delivering impact blows to the shank of a drill steel, a member supporting the steel in line therewith, means/rendering the rotation effective uponeither stroke ofthe piston, and additional means actuated by the rotation means on vthe non-rotating stroke of' the piston to move thel drill longitudinally of the support.

4. In a rock drill, the combination ofl'a supporthaving 'slidable thereon a cylinder and a reciprocating piston hammer within the cylinder for delivering impactv blows to the shank of a'.` drill steel, a member supporting the steel in line with the piston and having interlocking relation therewith, means. for rotating the piston during its reciprocation, said means including a rifle.-

' bar, selectively operated pawls engageable with with the piston and having interlocking relation the rifle bar for determining the stroke uponwhich rotation is effected, and means operated by the non-rotating stroke of the piston to. move the drill longitudinallyof the support.

5. In a rock drill,- the combination of a supportr having slidable thereon a: cylinder and a reciprocating pistony within the cylinder. for delivering. impact blows to the shank of a Ydrill steel, a membersupporting the steel in line with the pis-I ton and having interlocking relation therewith, av rifle barinterlockedY with the piston and havingv the usualiratchet pawls, a ring engageab-le by the pawls and rotated therewith under certain conditions, means Aforfl'ocking the ring against. rotation, a feed screw within the support, a feed nut carried by the drill and in threaded engagement with-,the feed screw, a driving connection between the riiie bar and the feed nut, and a controlling element engageable with .the ratchet ring and driving means for selecting the direction of rotation of the feed nut.

6. In a rock drill, the combination of a support having slidable thereon a cylinder and a reciprocating piston within the cylinder for delivering impact blows to the shank of a drill steel, a member supporting the steel in line with the piston and having interlocking relation therewith, a rotation mechanism carried by the drill and interlocked with the piston, said rotation mechanism including a rifle bar and a pawl carrying head, a ratchet engageable by pawls of the head, a feed screw in the support, a feed nut carried by the drill and in threaded engagement with the feed screw, a driving connection between the rifle bar and the feed nut, and common means engageable with the rotation mechanism and driving connection for controlling the direction in which the feed nut rotates upon 'certain movement of the piston.

7. In a drilling apparatus, the combination of a guide shell and a drilling motor slidable thereon, a feed screw supported in the shell for free rotation, means carried by the motor and operating on the feed screw for moving the drill on the shell, and meansl on the guide shell and engagea-ble with the screw for determining the speed at which the motor moves.

8. In a drilling apparatus, the combination of a guide shell and a drilling motor slidable thereon, a feed screw mounted within the shell for free rotation, means carried by the motor and operating on the feed screw for moving the drill on the shell, and frictional means carried by the shell and engageable with the feed screw for de-- termining the speed at which the motor moves.

9. In a drilling apparatus, the combination of a guide shell and a drilling motor slidable thereon, said motor including a reciprocating piston, a feed screw rotatably mounted in the shell, frictional means controlled by the operator for determining the speed in which the screw rotates, and a connection between the piston and the feed screw for moving the drill longitudinally of the shell at a speed determined by the frictional engagement of the feed screw with theV shell. v

10. In a drilling apparatus, the combination of a guide shell and a drilling motor slidable thereon, a reciprocating piston within the motor, a feed nut carried by the motor and rotated by the piston, means for selectively determining thedirection in which the feed nut rotates,- a feed screw supported by the guide shell and engageable with the feed nut, frictional means for locking the feed screw to the shell, and said means being controllable by the operator to determine the speed at which the drillmoves longitudinally of the guide shell.

11. In a drilling apparatus, the combination of a guide shell and a drilling motor slidable thereon, a reciprocating'piston within the motor, a feed nut carried by the motor and rotated by the piston, means for selectively determining the direction in which the feed nut' rotates,v a feed screw mounted for free rotation within the guide` shell, frictional means for locking the screw. to the shell to insure movement of thedrill upon rotation of the feed nut, and manually operated means for controlling the degree of frictional engagement between the shell and screw to regulate the speed at which the drill moves.

12. In a drilling apparatus, the -combination of a guide shell and a drilling motor slidable4 thereon, a reciprocating piston within the motor, a feeding mechanism for the motor including a feed nu-t carried thereby and rotated by the piston, a feed screw engageable by the feed nut and mounted for free rotation within the guide shell, and Variable means for locking the screw to the shell to insure a maximum and a minimum speed of movement of the Vmotor upon rotation of the feed nut. Y

13. In a drilling apparatus, the combination of a guide shell and a drilling motor slidable thereon, a reciprocating piston within the motor, a feeding mechanism for the motor including a feed nut carried thereby andrrotated by the piston, a feed screw engageable by the feed nut and mounted for free rotation with the guide shell, and operable means variably locking the screw to the shell to insure movement of the motor thereupon at any desired speed upon the continued operation of the feeding means.

14. In a drilling apparatus, the combination of a guide shell and a .drilling motor slidable thereon, a reciprocating piston within the motor, a feeding mechanism for the motor including a feed nut carried thereby and rotated by the piston, a feed screw engageable by the feed nut and mounted for free rotation with the guide shell, and variable means for locking the screw to the shell to insure a maximum and minimum speed of movement of the motor upon the nonvariable rotation of the feed nut. p

BARTON R. SHEETS. 

